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## entrNumerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bendNumerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend

#### MOHAMMAD VAGHEFI [1] , MOHAMMAD SHAKERDARGAH [2] , MARYAM AKBARI [3]

A spur dike is a structure that projects from a stream bank into the river channel and causes a redirection of flow away from the bank toward the tip of the spur dike. Construction of a spur dike against the flow causes significant changes in flow pattern in the channel. In this study, the flow pattern around a 25% submerged T-shaped spur dike in a 90$^{\circ}$ bend with rigid bed and various Froude numbers 0.2, 0.34, 0.45, and 0.6 was examined using FLOW-3D software. Numerical results were compared with experimental results and analyzed. The results indicated that in cross section around the spur dike, when Froude number increases, the formed vortexes decreased by 35%. Longitudinal velocity and lateral velocity increased twice as much as their former values. The highest amount of vertical velocity was observed between the wing of the spur dike and the external bend, and closer to the external bend, with an increase in Froude number, vertical velocity components variations decreased by 33%. Moreover, the results indicated that when the Froude number increases, the width of the separation zone increases, but the change in the length of the separation zone in different levels is negligible.
A spur dike is a structure that projects from a stream bank into the river channel and causes a redirection of flow away from the bank toward the tip of the spur dike. Construction of a spur dike against the flow causes significant changes in flow pattern in the channel. In this study, the flow pattern around a 25% submerged T-shaped spur dike in a 90$^{\circ}$ bend with rigid bed and various Froude numbers 0.2, 0.34, 0.45, and 0.6 was examined using FLOW-3D software. Numerical results were compared with experimental results and analyzed. The results indicated that in cross section around the spur dike, when Froude number increases, the formed vortexes decreased by 35%. Longitudinal velocity and lateral velocity increased twice as much as their former values. The highest amount of vertical velocity was observed between the wing of the spur dike and the external bend, and closer to the external bend, with an increase in Froude number, vertical velocity components variations decreased by 33%. Moreover, the results indicated that when the Froude number increases, the width of the separation zone increases, but the change in the length of the separation zone in different levels is negligible.
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Primary Language tr Articles Author: MOHAMMAD VAGHEFI Author: MOHAMMAD SHAKERDARGAH Author: MARYAM AKBARI Publication Date : February 1, 2014
 Bibtex @ { tbtkengineering145616, journal = {Turkish Journal of Engineering and Environmental Sciences}, issn = {1300-0160}, eissn = {1303-6157}, address = {}, publisher = {TUBITAK}, year = {2014}, volume = {38}, pages = {266 - 277}, doi = {10.3906/muh-1405-2}, title = {Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90\$\^\{\\circ\}\$ bend}, key = {cite}, author = {VAGHEFI, MOHAMMAD and SHAKERDARGAH, MOHAMMAD and AKBARI, MARYAM} } APA VAGHEFI, M , SHAKERDARGAH, M , AKBARI, M . (2014). Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend. Turkish Journal of Engineering and Environmental Sciences , 38 (2) , 266-277 . DOI: 10.3906/muh-1405-2 MLA VAGHEFI, M , SHAKERDARGAH, M , AKBARI, M . "Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend". Turkish Journal of Engineering and Environmental Sciences 38 (2014 ): 266-277 Chicago VAGHEFI, M , SHAKERDARGAH, M , AKBARI, M . "Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend". Turkish Journal of Engineering and Environmental Sciences 38 (2014 ): 266-277 RIS TY - JOUR T1 - Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend AU - MOHAMMAD VAGHEFI , MOHAMMAD SHAKERDARGAH , MARYAM AKBARI Y1 - 2014 PY - 2014 N1 - doi: 10.3906/muh-1405-2 DO - 10.3906/muh-1405-2 T2 - Turkish Journal of Engineering and Environmental Sciences JF - Journal JO - JOR SP - 266 EP - 277 VL - 38 IS - 2 SN - 1300-0160-1303-6157 M3 - doi: 10.3906/muh-1405-2 UR - https://doi.org/10.3906/muh-1405-2 Y2 - 2020 ER - EndNote %0 Turkish Journal of Engineering and Environmental Sciences Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend %A MOHAMMAD VAGHEFI , MOHAMMAD SHAKERDARGAH , MARYAM AKBARI %T Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend %D 2014 %J Turkish Journal of Engineering and Environmental Sciences %P 1300-0160-1303-6157 %V 38 %N 2 %R doi: 10.3906/muh-1405-2 %U 10.3906/muh-1405-2 ISNAD VAGHEFI, MOHAMMAD , SHAKERDARGAH, MOHAMMAD , AKBARI, MARYAM . "Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend". Turkish Journal of Engineering and Environmental Sciences 38 / 2 (February 2014): 266-277 . https://doi.org/10.3906/muh-1405-2 AMA VAGHEFI M , SHAKERDARGAH M , AKBARI M . Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend. Turkish Journal of Engineering and Environmental Sciences. 2014; 38(2): 266-277. Vancouver VAGHEFI M , SHAKERDARGAH M , AKBARI M . Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90$^{\circ}$ bend. Turkish Journal of Engineering and Environmental Sciences. 2014; 38(2): 277-266.

Authors of the Article
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[2]
[3]